Pattern of cross‐resistance in pyrethroid‐selected populations of Helicoverpa armigera Hübner (Lep., Noctuidae) from India

Abstract

In Helicoverpa armigera, withdrawal of selection pressure resulted in a two-to fourfold increase in susceptibility to synthetic pyrethroids and continuous selection enhanced the resistance level by four-to fivefold to the respective pyrethroids at the end of the 14th generation. Populations selected for resistance to one pyrethroid showed positive cross-resistance to all other pyrethroids, but no cross-resistance to endosulfan and thiodicarb. There was a significant increase in mixed-function oxidase activity with advancing generation suggesting its possible role in the positive cross-resistance among the pyrethroids. The induction of carboxyl esterases in pyrethroid-selected populations may have resulted in the activation of indoxacarb, thereby accounting for the observed negative cross-resistance.

Bioefficacy of flindersine against Helicoverpa armigera Hübner, Spodoptera litura Fabricius, Anopheles stephensis Liston. and Culex quinquefasciatus Say.

“…It also attacks more than 100 crops (Talukder and Howse 1994). Both H. armigera and S. litura have developed resistance against synthetic pesticides (Kumar and Reghupathy 2001;Ramasubramaniam and Regupathy 2004). Mosquitoes are responsible for spreading diseases like malaria, Japanese encephalitis, yellow fever, dengue and filariasis.…”

Esterase-based metabolic resistance to insecticides in heliothine and spodopteran pests

“…40,54) Significantly, the correlation between esterase activity and the degree of resistance was shown to hold up when an Indian population was selected for increased SP resistance in the laboratory: esterase activity increased in parallel with resistance over the course of selection. 51) Some authors have also suggested that the role of the esterases relative to P450s may have been underestimated in the (many) cases where a contribution from P450s to the resistance has been inferred from synergism data with the P450 inhibitor PBO. This is because H. armigera esterases are also inhibited by PBO.…”

“…The association is particularly strong in data for populations from Australia, [39][40][41][42] south and southeast Asia [43][44][45][46][47][48][49][50][51] and central Africa 52,53) and is also significant in Chinese populations, 46,54,55) although it has not been found in west African populations. [56][57][58] Whether this geographic variation in the strength of the associations reflects genetic differences among populations or methodological differences among investigators is moot, although some effect of genetic differences seems likely.…”

“…22) Interestingly, there is evidence that esterase-mediated SP resistance in H. armigera leads to negative cross-resistance to the oxadiazine indoxacarb. 51,77) Indoxacarb has two ester bonds and it appears that esterase action is required to activate the compound in vivo. Higher esterase activities in SP resistant lines therefore lead to their greater sensitivity to indoxacarb.…”

Synthetic Pyrethroid Resistance in Field Strains of Helicoverpa armigera (Hubner) (Lepidoptera: Noctuidae) in Tamil Nadu, South India

“…[23] reported high level of resistance to fenvalerate and deltamethrin. Tamilselvi [24] , Niranjankumar [25] and Ramasubramanian [26] recently confirmed the high level of resistance to deltamethrin, cypermethrin, lambdacyhalothrin, fenvalerate and beta-cyfluthrin in Tamil Nadu. The resistance development due to exposure of earlier compounds was reported from different parts of India [4,13,15,[27][28][29][30][31][32][33][34][35][36] .…”